1. Field of the Invention
The present invention relates to an insertion/removal apparatus for estimating a manipulation amount such as an insertion/removal amount and a rotation amount of an insertion section that is inserted into an observation target object, and a method for estimating a direct manipulation of the insertion section, and a storage medium which non-transitory stores a program for estimating a direct manipulation of the insertion section.
2. Description of the Related Art
There is an apparatus for performing an operation inside an observation target object by inserting an insertion section into the observation target object through a thin tube hole. For example, an endoscope is intended to observe the inner surface of an observation target object by inserting an insertion section into the observation target object. An apparatus such as the endoscope makes it impossible to observe, e.g. the shape of an insertion section in a tube directly from the outside. Therefore, an operator of the apparatus needs to observe the inner surface of an observation target object while imagining a state of the insertion section in the tube.
In the endoscope, however, the state of the insertion section, such as the position and shape thereof, in the observation target object cannot be seen from outside the observation target object. Thus, an operator needs to make an observation while imagining where in the tube hole the insertion section is located and what is observed at the present time regarding the state of the insertion section inserted into the tube hole. In short, an operator needs to manipulate the insertion section by intuition while imagining the state of the insertion section inside the observation target object.
As is seen from the above, when the shape of a tube hole is complex or when an observation target object is soft and deformed like a living body, the insertion into the observation target object itself could be difficult. When a tube hole differs in position or shape from what an operator imagined, it is likely to exert an influence on the observation target object as a worst case. Therefore, the operator needs to improve his or her operation skill, such as long hours of training for operation and gaining of intuition and experience during the actual operation. In other words, if an operator is not a highly-trained technician or expert, he or she could not insert the insertion section into the observation target object or perform an operation in the observation target object.
Under the circumstances described above, a technique of notifying an operator of the state of an insertion section in a tube hole is devised. For example, Jpn. Pat. Appln. KOKAI Publication No. 2007-044412 discloses an endoscope insertion shape probe for detecting a shape of an insertion section of an endoscope and displaying it. The endoscope insertion shape detection probe is inserted into a forceps channel provided in an endoscope apparatus to detect the shape of the insertion section of the endoscope. The endoscope insertion shape detection probe irradiates a mirror with light supplied from a light supply fiber and transmits the light reflected by the mirror through a plurality of curvature detection optical fibers. Each of the curvature detection optical fibers is provided with one optical loss section that varies in optical loss according to a corresponding curvature. Accordingly, the light guided by each of the curvature detection optical fibers reaches a module via the optical loss section. It is thus possible to detect the curvature of a curvature detection optical fiber in a position where the optical loss section is provided, by detecting a change of intensity of the light guided to the module.
Jpn. Pat. Appln. KOKAI Publication No. 2007-044412 also discloses using a plurality of curvature detection fibers whose optical loss sections are provided in different positions to detect the curvatures of the curvature detection fibers at the different positions of the optical loss sections, respectively. It is thus possible to detect the shape of an endoscope insertion section in accordance with the bending angle at a point where each optical loss section is provided and the distance between adjacent points.